Compilare: main.cpp: In function 'int main()': main.cpp:32:18: warning: array subscript has type 'char' [-Wchar-subscripts] 32 | freq[ch]++; | ^~ main.cpp:37:28: warning: array subscript has type 'char' [-Wchar-subscripts] 37 | s.insert({freq[ch], ch}); | ^~ main.cpp:54:25: warning: array subscript has type 'char' [-Wchar-subscripts] 54 | if(freq[ch] && ch != str[i]) | ^~ main.cpp:62:29: warning: array subscript has type 'char' [-Wchar-subscripts] 62 | if(freq[ch] == maxx || maxx <= (len - 1) / 2) | ^~ main.cpp:71:39: warning: array subscript has type 'char' [-Wchar-subscripts] 71 | s.erase({freq[ch], ch}); | ^~ main.cpp:72:30: warning: array subscript has type 'char' [-Wchar-subscripts] 72 | freq[ch]--; | ^~ main.cpp:73:40: warning: array subscript has type 'char' [-Wchar-subscripts] 73 | s.insert({freq[ch], ch}); | ^~